Abstract
Objective
To evaluate the clinical efficacy and tolerability of pembrolizumab in combination with bevacizumab and oral metronomic cyclophosphamide in heavily pretreated patients with platinum-resistant ovarian cancer in a real-world setting.Methods
This retrospective study included patients with platinum-resistant or refractory epithelial ovarian, fallopian tube, or primary peritoneal carcinoma treated with pembrolizumab, bevacizumab, and oral metronomic cyclophosphamide at a single academic institution from January 2019 through April 2025. The primary endpoint was the objective response rate. Secondary endpoints included the disease control rate, clinical benefit rate at 24 weeks, progression-free survival, overall survival, and treatment discontinuation due to toxicity.Results
Forty patients were evaluable for response and toxicity. Median age was 65 years, and 75.6% had high-grade serous histology. Patients were heavily pretreated with a mean of 3.6 prior lines of therapy. The objective response rate was 7.5%, while 52.5% achieved stable disease, yielding a disease control rate of 60%. The clinical benefit rate at 24 weeks was 30.0%. Median progression free survival was 3.3 months and median overall survival was 7.8 months. Two-thirds of patients experienced adverse events with 12.5% of patients discontinuing at least 1 drug due to toxicity.Conclusions
This regimen produced a low objective response rate in a real-world cohort. With the emergence of newer FDA-approved regimens for PROC, the clinical role of pembrolizumab, bevacizumab, and oral cyclophosphamide has narrowed. However, it may remain an appropriate option for select patients who are ineligible for or have progressed after therapies supported by randomized evidence.